The present invention relates to a cereal grain sorting system capable of selectively and completely removing foreign materials such as coats, stem pieces, various seeds like mustard seeds and grass seeds, corn, dust, waste, stones, and metal pieces, or defective products such as worm-eaten beans, broken beans, and cracked beans from cereal grains such as soybeans or red beans, and to a roll sorting machine which can be incorporated in the cereal grain sorting system.
Conventionally there has been used a sorting system comprising a rough sorting machine, a specific gravity sorting machine, and a spiral sorting machine for selectively removing foreign materials such as coats, stem pieces, various seeds like mustard seeds and grass seeds, corn, dust, waste, stones, and metal pieces, or defective products such as worm-eaten beans, broken beans, and cracked beans from cereal grains such as soybeans or red beans.
In this sorting system, foreign materials having different grain diameters from a specified one are selectively removed by the rough sorting machine, those having different specific gravities from a standard one are selectively removed by the specific gravity sorting machine, and also those having different mass from a standard one are selectively removed with the spiral sorting machine by making use of the centrifugal speed, and thus foreign materials and defective products are removed from the feedstock cereal grains.
However, when the specific gravity sorting machine requiring a large volume of air is operated for a long time in a sorting plant where 5 to 20 tons of cereal grains not having been sorted yet in the very dusty atmosphere, clogging occurs in a cover for protecting the machine, or cracked beans drop to a section under the screen and are clogged between static airflow adjusting plates so that the sorting state always changes, and when the airflow becomes smaller, light weight foreign materials are mixed in acceptable products, which remarkably lowers the sorting precision, and therefore it is required for the operator to always monitor and adjust the machine or to clean the machine, and the work load is very heavy. In addition, the specific gravity sorting machine requires a large volume of air to be supplied, which not only makes a cloud of dust and worsens the working environment, but also causes heavy noises of 100 phons or more.
In the spiral sorting machine, cereal grains are dropped along a circular inclined surface and foreign materials having different mass from the cereal grains are selectively removed by making use of the centrifugal speed, but adjustment for a size and a shape (flatness) of the feedstock cereal grains is not possible at all, so that the sorting precision is rather low, and in addition, foreign materials such as corns, broken beans, and stone pieces are collided by acceptable products continuously flowing along the inclined surfaces and are pushed out to the acceptable product side to be mixed therein, and when the centrifugal speed drops due to the effect of dust or others in the atmosphere at the working site, the acceptable products may be mixed in foreign materials, which may in turn lowers the yield.
Further in the sorting system as described above, dust raised by the specific gravity sorting machine are deposited around acceptable products, so that the acceptable products become dusty, and in addition, as the spiral sorting machine is a internally sealed type of device, dust is easily deposited inside the machine, and the dust released from the specific gravity sorting machine may cause operation fault or other troubles of the spiral sorting machine, and therefore the operational stability in long time use is rather low.
As a roll sorting machine which can be incorporated in a cereal grain sorting system, there has been known one in which an endless belt is hung over a lower roll and an upper roll positioned in parallel to and diagonally above the lower roll and the upper roll is rotated so that a top surface of the belt moves to the upper roll. Also, there has been known another one in which the endless belt is oriented in the traveling direction or in a direction perpendicular to the traveling direction (Japanese Patent Publication No. SHO 31-1361).
The present applicant has conducted hard and strenuous research and development efforts in the field of roll sorting machine, and developed several novel sorting machines including one capable of completely separating not only foreign materials which have flat, angular, or irregular spherical forms and can not rotate, but also defective products such as cracked beans and worm-eaten beans which have similar spherical forms as regular spherical forms and can rotate from spherical bodies such as soybeans, red beans, and pearls each having a spherical form, in which the distance required for sorting may be short and can be built in a compact form because the twisted curved surface of the endless belt is utilized and also which can smoothly sort a large quantity of soybeans or the like (Japanese Patent Publication No. SHO 57-28307). Another one capable of accurately sorting not only foreign materials having flat or angular forms, but also those like cracked beans or worm-eaten beans which can rotate, enabling free and smooth adjustment for discharge percentages of sorted materials to an outlet for acceptable products and a second outlet for rejected products or foreign materials according to an open/close degree of a separation means, which can efficiently be formed into a multi-stage device with a short sorting distance and can be built in compact form, and also which can efficiently screen a large volume of feedstock soybeans because it can easily treat the feedstock soybeans piled up when fed with a saw-toothed plate (Japanese Patent Laid-Open Publication No. HEI 10-165895).
However, in the conventional type of roll sorting machine, 1) as a supply rate of cereal grains from the feedstock cereal grains is not stable, sometimes cereal grains as overflow from the inlet of the feedstock cereal grains may clog, and when a quantity of cereal grains surpassing the processing capacity of the machine is supplied even temporally, the sorting precision may become remarkably lower. 2) Cereal grains such as soybeans have an oval form, and in the case of cereal grains having an oval form, when a moving speed of a belt reaches a prespecified speed, each piece of the cereal grains rises up and starts rotating, which makes roll sorting possible, but a belt speed optimum for starting rotation varies according to forms of the cereal grains, and therefore the sorting precision varies according to types of the cereal grains. 3) In case of a multiple stage roll sorting machine in which a plurality of roll sorting machines are piled up in the multiple stages, sprocket wheels of upper rolls of respective stages are linked to each other with a chain, and the belts in the multiple stages are moved simultaneously with one driving force source. Because of this configuration, when a number of stages is large, the chain becomes longer and troubles easily occur. Further, when oil is supplied for maintenance of the chain, sometimes the oil may spatter to contaminate the feedstock cereal grains, and if the chain is left uncovered after the maintenance, it is very dangerous, which is disadvantageous for the safety of operators.
The present invention was made to solve the problems described above, and it is an object of the present invention to provide a cereal grain sorting system which allows stable operations for a long time without requiring supply of a large quantity of air, and which can provide high quality final products relatively quietly and keeping the sorting precision and high production yield without further worsening the working conditions.
The present invention was made also to solve the problems of the roll sorting machine described above, and it is an object of the present invention to provide a roll sorting machine which can insure safety for workers and also can prevent the sorting precision from varying due to differences of forms of cereal grains without causing the fed feedstock cereal grains to overflow from or clog the inlet of the sorting machine, without lowering the sorting machine caused by supply of a large quantity of cereal grains surpassing a regular throughput of the sorting machine, and further without causing contamination of the cereal grains.
To solve the problems in the cereal grain sorting system as described above, the cereal grain sorting system according to the present invention comprises a wind force sorting process of selectively removing light weight foreign materials from feedstock cereal grains, a rough sorting process of selectively removing foreign materials having different diameters from the feedstock cereal grains, and a roll sorting process of selectively removing foreign materials having different forms from the feedstock cereal grains having been subjected to the wind force sorting process and the rough sorting process.
In the cereal grain sorting system according to the present invention, when magnetic foreign materials such as metal pieces are mixed in the feedstock cereal grains, the magnetic foreign materials can selectively and efficiently be removed by providing a magnetic force sorting process, and this configuration is a preferable mode.
Further in the cereal grains sorting system according to the present invention, when stone pieces are mixed in the feedstock cereal grains, the stone pieces can efficiently be removed by further providing a stone-piece removal process of selectively removing the stone pieces from the feedstock cereal grains, which is preferable.
In the cereal grain sorting system according to the present invention, when fine materials such as dust and mud are deposited on the feedstock cereal grains, by further providing a polishing process of removing the fine deposited materials from the feedstock cereal grains by polishing, the fine deposited materials such as dust and mud can efficiently be removed, which is more preferable.
In the cereal grain sorting system according to the present invention, when it is necessary to sort the final products according to grain diameters, by further providing a grain diameter sorting process of sorting the feedstock cereal grains according to the grain diameters, it is possible to sort the final products according to the gain diameters, which makes it possible to advantageously supply the final products sorted according to the grain diameters to satisfy the consumers"" demands.
To solve the problems in the roll sorting machine described above, in the roll sorting machine according to the present invention, an endless belt is hung over a lower belt and an upper roll positioned diagonally above the lower roll, the lower roll and upper roll are inclined in the same direction at prespecified angles respectively with the inclination angle of the lower roll smaller than that of the upper roll. Further one or more saw-toothed plates are provided on a top surface of the endless belt, and, at the same time, a lengthy inclined discharge plate inclining downward in the sideward direction is provided at a side edge in the downwardly inclining side of the endless belt. This roll sorting machine according to the present invention is characterized in that a constant rate supply unit for supplying feedstock cereal grains at a specified constant rate to a feedstock cereal grain inlet is provided so that feedstock cereal grain supply rate can freely be adjusted.
Further, in the roll sorting machine according to the present invention, an endless belt is hung over a lower roll and an upper roll positioned diagonally above the lower roll, the lower roll and upper roll are inclined in the same direction at prespecified angles respectively with the inclination angle of the lower roll smaller than that of the upper roll. Further, one or more saw-toothed plates are provided on a top surface of the endless belt, and, at the same time, a lengthy inclined discharge plate inclining downward in the sideward direction is provided at a side edge in the downwardly inclining side of the endless belt. This sorting machine is characterized in that a speed-variable driving force source for changing a driving speed of the endless belt is provided and the driving speed for the endless belt can freely be changed or adjusted according to forms of fed feedstock cereal grains so that the feedstock cereal grains rotate and drop.
Still further, in the roll sorting machine according to the present invention, an endless belt is hung over a lower roll and an upper roll positioned diagonally above the lower roll, the lower roll and upper roll are inclined in the same direction at prespecified angles respectively with the inclination angle of the lower roll smaller than that of the upper roll. Further, one or more saw-toothed plates are provided on a top surface of the endless belt, and, at the same time, a lengthy inclined discharge plate inclining downward in the sideward direction is provided at a side edge in the downwardly inclining side of the endless belt. This roll sorting machine is characterized in that a constant rate supply unit for supplying feedstock cereal grains at a prespecified rate to a feedstock cereal grain inlet, and a supply rate of the feedstock cereal grains can freely be adjusted. Further, a speed-variable driving force source for changing a driving speed for the endless belt is provided and the driving speed for the endless belt can freely be changed or adjusted according to forms of fed feedstock cereal grains so that the feedstock cereal grains rotate and drop.
In the roll sorting machine, when the constant rate supply unit is a vibration type of constant rate supply unit for supplying the feedstock cereal grains at a specified constant rate with vibration, a more stable and a more uniformed constant supply of feedstock cereal grains can advantageously be performed.
In the roll sorting machine, when the speed-variable driving force source is a direct linkage type of speed-variable driving force source directly connected to an edge of this upper roll, use of a chain is not required, so that the problems such as chain troubles, contamination of the feedstock cereal grains, and those concerning the safety for operators are advantageously eliminated.
In the roll sorting machine, by monitoring the cereal grains fed onto an upper surface of the endless belt by a monitor camera as to whether the cereal grains are rotating in the acceptable state and adjusting a driving speed for the endless belt so that the cereal grains rotate and drop, it is to perform optimum roll sorting suited for forms of various types of cereal grains. Further, it is possible to maintain the sorting precision even if various types of cereal grains are fed, which is more preferable.
Further in the roll sorting machine, by monitoring the cereal grains fed onto an upper surface of the endless belt by a monitor camera as to whether the cereal grains are rotating in the acceptable state and adjusting inclination angles of the upper roll and lower roll as well as an angle between a central axis of the upper roll and that of the lower roll respectively, it is possible to insure optimal conditions for roll sorting, which is advantageous.
Further, when the roll sorting machine is embodied as a multiple stage roll sorting machine formed by stacking the roll sorting machines in multiple stages in which a speed-variable driving force source is provided for an upper roll in each stage respectively so that a driving force for the endless belt for each stage can freely be adjusted and changed, an optimum rotating speed for the cereal grains supplied thereto can be realized for each stage, and because of this configuration, the roll sorting machine can treat various types of cereal grains more flexibly.
Further when the roll sorting machine is embodied as a multiple stage roll sorting machine in which a constant rate supply unit for supplying cereal grains to feedstock cereal grain inlet for each stage so that a supply rate of the feedstock cereal grains can freely be adjusted, it is possible to supply the feedstock cereal grains to each stage under stable and uniform conditions, which is more preferable.
Further, when a roll sorting process is carried out with the roll sorting machine in a cereal grain sorting system, the cereal grain sorting system becomes more advantageous in terms of its sorting precision, operational stability, and safety during operations.